Peroxyacetic acid (pK_a = 8.2) is a much weaker acid than acetic acid (pK_a = 4.74). Explain why peroxyacetic acid is a weaker acid than acetic acid.

For the bases shown, draw the conjugate acid and identify a pK_a value from Table 4.5 that would help you accurately estimate its stability.

(e)

Hydrogen gas (H₂) has a relatively high pK_a value. Is it a stable or unstable acid? Do you expect it to participate in acid–base reactions?

Arrange each group of compounds in order of increasing basicity.

c. sodium benzoate, sodium ethoxide, and sodium phenoxide

d. pyridine, sodium ethoxide, and sodium acetate

Hydrogen peroxide (HOOH) has a pK_a of 11.6, making it roughly 10,000 times as strong an acid as water (pK_a = 15.7). Explain why H₂O₂ is a stronger acid than H₂O.

Give the pK_a value of the following compounds.

b.

Using the table of pK_a values given in [Appendix I], answer the following:

a. Which is the most acidic organic compound in the table?

b. Which is the least acidic organic compound in the table?

c. Which is the most acidic carboxylic acid in the table?

For the bases shown, draw the conjugate acid and identify a pK_a value from Table 4.5 that would help you accurately estimate its stability.

(c)

For each indicated proton, suggest an approximate pK_a value from Table 4.5. Rationalize your choice.

(b)